New Zealand’s Mycoplasma bovis eradication campaign has now been running for almost three years, with no decline in the number of farms newly detected as being infected. Can the disease be stamped out?

New Zealand’s Mycoplasma bovis eradication campaign has now been running for almost three years, with no decline in the number of farms newly detected as being infected. Can the disease be stamped out?

It is now more than five months since I last wrote about Mycoplasma bovis in late October 2019. Since then, another 44 farms have gone positive, bringing the total to 245 farms since the disease was discovered in July 2017. All of these farms have been required to slaughter their herds. There are 31 farms where that process is still ongoing.

During this latest five-month period, farms infected with Mycoplasma bovis have been identified at the average rate of two per week. This is slightly higher than the overall average rate of 1.75 farms confirmed per week since the disease was first discovered in July 2017.

This raises a legitimate question as to whether it is the Ministry of Primary Industries (MPI) or the disease that is running faster? Has MPI got better at their job of finding infected farms, or is it because the disease is running ahead and leaving increased calling-cards behind?

I am often asked as to whether or not Mycoplasma bovis can be eliminated. I have always been sceptical. Right now, I still do not know. There is definitely a chance, but the evidence remains murky.

Ever since the Government gave the full steam ahead decision back in April 2018, the official line has been that the program is going well. Then, in April 2019 we learned that things had in fact not been going well at all, but would supposedly go well thereafter. That was when MPI announced that there would be a big ‘surge’ in activity.

April 2018 was also when we learned that the official figures had been fudged over at least the previous five months, with MPI using one criterion to decide whether herds should be considered infected and slaughtered, but using another criterion, and hence a totally different number, to disclose to the public. Quite simply we had been manipulated and lied to.

Those of us close to the on-farm action had known for many months, indeed right from the outset, that MPI had been fudging and hiding their gross inefficiencies. However, we found it more than a little challenging to communicate our concerns to the authorities. It was something the Director General of MPI at that time, a former military man who by instinct and training relied on information passed to him through the formal system, did not wish to acknowledge.   He did respond, but through personal attacks on the messenger rather than dealing with the issues.

A problem with fudged figures, including mid-level underlings hiding their own inefficiencies, is that top officials themselves can get misled. In many organisations, the top people are the last people to know when things are going wrong unless they also have informal networks. 

In the case of MPI and Mycoplasma bovis, it also meant that the Minister was not getting the full story. But the Minister did inform me very firmly one day in his office that he believed the formal information that he was getting was correct, and anything I might say publicly about program defects was not helpful, and risked the ongoing social licence from the community to keep the program going.

When the new Director General of MPI took over in late 2018, he quickly recognised by talking to farmers and other people in the field that there were many problems, but it still took time for full recognition to develop that he was getting fed the same mushroom treatment (animal fertiliser and darkness) as the rest of us.

Since then, MPI has had a major makeover and the public face of MPI in relation to Mycoplasma bovis is a different set of people than previously. The people away from the public eye have also changed considerably.

One of the advantages of the new guard is that they no longer have to dig bigger and bigger holes for themselves while trying to defend and cover up prior fudgings.  However, those matters of fudgings and laying blame for the past do still have to be handled with discretion. Anything else would not be a good career move.

Those of us from an older generation who used to watch ‘Yes Minister’ and then ‘Yes Prime Minister’ got many a laugh from the parodies of government and bureaucracies. A friend of mine who was himself a mandarin within that English system tells me it was all so true.  In fact, the traits are universal.

So the question becomes, when the new guard says that they are cautiously optimistic about eradicating Mycoplasma bovis, can we trust them given the way the old guard behaved? My judgement is that we can, as long as due weight is given to the fact that these people at the top are indeed still cautious in their assessment, and there are still lots of unknowns.

In contrast, when the messaging comes from within the industry organisations, they are still driven by maintaining social licence from their members. In any case, the industry spin doctors don’t really know themselves, as they are simply communicators.

So, now a little more as to where we are in a technical sense.

The key question is whether or not the ‘estimated dissemination rate’ (EDR) between herds, which is essentially the same concept as R, the transmission rate for COVID-19 between people, has been driven down below ‘1’? An EDR of ‘1’ is the crucial separation point that determines whether or not the disease will proliferate or fade away.

Alternatively worded, does each infected farm on average infect more or less than one other farm?  Eventual outcomes depend totally on what is the correct answer to that question.

One thing we do know is that the bulk-milk ELISA testing of every dairy farm each month is a powerful tool for filtering out those dairy farms that are likely to be infected and therefore need closer scrutiny. That tool was not available until around August 2018. Even then it still had to be validated in the field. Without it, we would have been stuffed.

It is notable that in the last five months only five dairy farms have gone positive, with 25 newly diagnosed farms being beef farms and 12 further farms being ‘other’ (mainly dairy youngstock). But some caution is appropriate with MPI sometimes shifting farms between categories and even transferring farms between islands! 

The biggest current unknown relates to whether Mycoplasma bovis has got into beef breeding-herds as well as finishing-herds, where it has been highly prevalent. With hindsight, we will be able to answer that question, but only with hindsight.

The biggest weakness right now is that too many service bulls with uncertain backgrounds are still coming back onto dairy farms from beef finishing-farms, where their purpose is to have some fun with the cows before being sent to slaughter. I am trying to get MPI to put more focus on that part of the system.

We also should never forget the distress that the program continues to impose on affected farm families. In contrast to diseases like tuberculosis that we continue to fight against for good reason, or the currently endemic Johne’s disease that we will have to fight in the future, Mycoplasma bovis is a minor disease that farmers elsewhere in the world simply live with.

*Keith Woodford was Professor of Farm Management and Agribusiness at Lincoln University for 15 years through to 2015. He is now Principal Consultant at AgriFood Systems Ltd. One of his interests is the epidemiology of both animal and human diseases. He can be contacted at Keith’s previous COVID-19 articles are available here.

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3 years. And that's just controlling the travel of a few cows - they don't try and shoot off to the beech for a surf.

I hope we can do better with the bat virus....

.. well not just the bat, hopefully soon anything of such this? no longer in traditional resto menu offering:

Interesting comment Rastus. Do you know what the most dangerous piece of equipment in most houses is? I'm pretty sure it is a ladder, more ACC claims relating to that than anything other than a motor car. When I wander around my neighbourhood I am seeing every second household involved in maintenance on their property, ladders up everywhere. Some on facebook, and I've got a list of 500 friends there. So ban on surf or outdoor activity thing is just nonsense on the pretence you might need to be rescued when you have all these people up ladders. Plus you are missing the civil rights issue, I'll probably post more on that as the weeks roll on. No point in saving a few lives if we come out of this having a government with new dictatorial powers.

Yes I agree with you - the pretence of the activity endangering rescuers is a nonsense. However I can accept that they must pretend it is to keep the masses at home. Sitting at home in this beautiful weather when I would be in the hills is very frustrating.

The principles of the epdiemiology are very similar for Mycoplasma bovis and COVID-19. At the heart of it lie isolation of infected or potentially infected herds (or people), lots of testing and moving quickly. MPI fell down badly in relation to all of those for the first 21 months. With Mycoplasma bovis, it is hader than for COVID because most animals don't get sick and the tests are even more unreliable than COVID tests with false positives and false negsatives. But yes, as you say, one advantage is that the cows don't sneak off to the beach. But they have been known to seek out friends down the road.

I was wondering if the expertise of the scientists who manage our incursions of hort and ag threats were enlisted to help with the virus? I would think their experience most useful.

I believe AsureQuality labs are being used for COVID-19, and this is supposedly causing some delays with the Mycoplasma bovis test results. Yes, there is some relevant expertise in MPI but I doubt that MoH would use it. Possibly one key person in particular that should be called upon. Health folk sometimes look askance at those with animal expertise, although the irony is that the animal specialists actually have a lot more experience in disease eradication campaigns of the COVID type than do the human health folk.

Well Keith? - now you can imagine, it's difficult enough to ID sick farm animals for certain germs, let alone to ID sick exotic animals.. to be consumed: eg. bats, snakes, pangolins.. thousands of them, difficult to detect, specially when animals is fully armored & asymptomatic.

It's obvious that being a geographically remote island nation means that "nasties", including both Mycoplasma and Covid, are caused by inadequate border controls especially at the airports; this must be addressed. It could be addressed by a tax levied on all persons and 'things of any description' entering the country; it could be staffed by some of those made redundant in the travel industry, or any other struggling industry, assuming they can meet certain criteria including the ability to be trained and to take their job very seriously.
With unbridled immigration New Zealand border controls have been seen as a 'soft touch' in the past.
I think that future tourists contemplating visiting New Zealand would rather we had particularly rigorous controls at our borders.
But there are two questions I would ask Keith's opinion on:

1. What responsibility should the individual airlines exercise in the future if there is another virus on the loose?

2. Is the rumour true that it was ex-European Union farmers that introduced Mycoplasma bovis into NZ?

1) Personally I think controls have to be the responsibility of a Governemnt entity
2) The most likely source of Mycoplasma bovis is semen that was imported through the correct channels by one of the professional semen companies. But nothing is certain and it is unfair to blame any specific company. The widespread notion that Mycoplasma bovis arrived here because of the actions of Kiwi farmers of Dutch origin is not supported by any evidence. Unfortunately, MPI's messaging led to that notion getting legs when it was totally unjustified. It is correct, however, that a significant number of Kiwi farmers of Dutch origin were some of the early confirmed cases and have borne the brunt of the general misfortune.

It sounds like famers might be better served by a more focused organisation funded and lead by the industry itself instead of relying on MPI.

I can only compare it to Tb that was a major 45 years ago when I milked cows . herds being decimated by testing that was controversial when many of them on being sent to the works showed no lesions at all . But it appeared tb had a remarkable ability to appear in new areas well away from any known infections . Tb despite millions being spent is still here and still costing heaps to eradicate obvious this will probably never happen

Yes, possums and possibly wild pigs have been a big complicating factor with Tb.

I had a friend who came upon hard times and got into the possum control business. They had gps trackers located every trap and some tissue taken for lab to check to see any were infected. They never released the info and as far as I know to this day its still top secret.
Great if you could dig up those results Keith. My friend went on to become one of the most cynical people ever ,on all things council or DOC, related.

Its a bit like the 6 tracked kea who 'likely' died from 1080, and DOC only recently considering adding bird repellent to it. How many years have they been using 1080 and been told that native birds are collateral damage?

Those that into strict vegetarians, probably won't support more money into this.. like now? we have more concern to the bug that might.. kill us, so let's eradicate this one first, all monetary gun blazing towards it.

The biggest issue is timeliness of action by MPI.
I had two farmers, both beef finishers, recently telling me of the lag between initial identification of risk cattle on their farms and MPI actually showing up or taking some action. These farms are on NOD. In one case it took three weeks, enough time if the farmer had chosen to onsell or dispose of the cattle. That is too long a lag to be effective. The other farmer has several nait numbers and could have chosen to unload through a 'clean' number but chose not to. Not every farmer is so considered when faced with these tough decisions.

Yes, I have just become aware this weekend of a case where NODs have not been issued for strong forward traces that were known several months ago. This is very frustrating. The farmers need to get rid of the animals, and can legally do so, but they know it is not the right thing to do. So this is costing them money because with no NOD there is no compensation. So this shows the system is still not working as it should.

Mbovis will have taken advantage of this. Its a fools errand when there are so many holes in this system of eradication. I am desperately hoping those in charge run the chinese virus eradication better.

NZ has now had three serious and expensive biosecurity incursions - PSA, m. bovis and COVID 19. While it would be unfair to MPI to blame them for the COVID incursion, it is their job to protect us from such incursions, whether they be of known or unknown origin. While it could be argued that it is impossible to prevent something whose origin is unknown, at the very least we need a border protection system that is capable of quickly tracing suspected vectors once the unknown has been revealed, and not be faffing around three years after the event. Perhaps if the PSA litigators are successful with their Supreme Court action and MPI is forced to accept financial liability for its failures, they (MPI ) will sharpen their act.

NZ public & current govt, would love to watch this - during the lock-down period: (C'mon it's from 2015!)